function switchSectionTab(btn, panelId) {
    document.querySelectorAll('.section-tab').forEach(function(t) { t.classList.remove('is-selected'); });
    document.querySelectorAll('.section-panel').forEach(function(p) { p.classList.remove('active'); });
    btn.classList.add('is-selected');
    var panel = document.getElementById(panelId);
    if (panel) panel.classList.add('active');
    history.replaceState(null, '', '#' + panelId);
}

(function() {
    var hash = window.location.hash.replace('#', '');
    if (hash) {
        var panel = document.getElementById(hash);
        var tab = document.querySelector('[data-tab="' + hash + '"]');
        if (panel && tab) switchSectionTab(tab, hash);
    }
})();

function downloadVersion(versionId) {
    fetch('/api/versions/' + versionId + '/download')
        .then(function(res) {
            if (!res.ok) throw new Error('Failed to get download URL');
            return res.json();
        })
        .then(function(data) {
            window.location.href = data.download_url;
        })
        .catch(function(err) {
            showToast(err.message || 'Download failed');
        });
}